In a wireless communication network, a high network throughput is required for establishing a good communication link between one or more Base Stations (BS) and one or more Mobile Stations (MS). As network throughput is inversely proportional to interference, lowering the interference results in increased network throughput. The uplink interference is usually reduced by performing a link adaptation at the uplink. The link adaptation is performed by changing a modulation and coding scheme (MCS) level associated with the uplink. Such a link adaptation results in higher uplink throughput.
Generally, the link adaptation involves selection of an appropriate MCS level based on quality of the uplink between a BS and a MS. The quality of uplink includes uplink interference and fading characteristics of the uplink. For improving the quality of the uplink, a higher MCS scheme is selected. As a result, there is an increase in transmission power required by the MS for transmitting the signal through the uplink. Hence, overall uplink interference may increase in the wireless communication network, as the signal is transmitted with high transmission power.
Link adaptation may also be performed by controlling power utilization of the MS. Generally, an Open Loop Power Control mechanism may be utilized for controlling the power. Controlling the power involves reducing transmission power required by MS for transmitting the signal through the uplink. This may lead to reduction of the overall uplink interference in the wireless communication network. However, reduction of the transmission power may affect the quality of the signal transmitted as the MCS level is lowered accordingly. Hence, a tradeoff between controlling the power utilization of the MS and lowering the MCS level is required to enable transmission of signals with good quality and low uplink interference at the same time.
There are existing methods for maintaining the tradeoff between controlling the transmitted power associated with the MS and lowering the MCS level. One of these methods involves identifying a permissible uplink interference in the wireless communication network and lowering the MCS level of all MSs in the wireless communication network by a fixed MCS level. However, this method does not consider criteria for the permissible uplink interference generated by individual MSs. Thus, an optimum MCS level may not be achieved for all the MSs in the wireless communication network.
Therefore, there is a need for a method and apparatus for modifying uplink MCS level of MSs in a wireless communication network by considering criteria for the uplink interference generated by the MSs in the wireless communication network.
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